def multiple_solver(self, G, sources, grounds, finitegrounds):
"""Solver used for advanced mode."""
Gsolve = G
if finitegrounds[0] != -9999:
Gsolve = G + sparse.spdiags(finitegrounds.T, 0, G.shape[0], G.shape[0])
##remove infinite grounds from graph
infgroundlist = np.where(grounds==np.Inf)
infgroundlist = infgroundlist[0]
numinfgrounds = infgroundlist.shape[0]
dst_to_delete = []
for ground in range(1, numinfgrounds+1):
dst = infgroundlist[numinfgrounds-ground]
dst_to_delete.append(dst)
#Gsolve = deleterowcol(Gsolve, delrow = dst, delcol = dst)
keep = np.delete(np.arange(0, sources.shape[0]), dst)
sources = sources[keep]
Gsolve = ComputeBase.deleterowcol(Gsolve, delrow = dst_to_delete, delcol = dst_to_delete)
self.state.create_amg_hierarchy(Gsolve, self.options.solver)
voltages = ComputeBase.solve_linear_system(Gsolve, sources, self.options.solver, self.state.amg_hierarchy)
del Gsolve
self.state.del_amg_hierarchy()
numinfgrounds = infgroundlist.shape[0]
if numinfgrounds>0:
#replace infinite grounds in voltage vector
for ground in range(numinfgrounds,0, -1):
node = infgroundlist[numinfgrounds - ground]
voltages = np.asmatrix(np.insert(voltages,node,0)).T
return np.asarray(voltages).reshape(voltages.size)
